Enhanced Low Field Magnetoresistance in La$_{0.67}$Ca$_{0.33}$MnO$_{3}$/La$_{0.5}$Ca$_{0.5}$MnO$_{3}$ superlattices

ORAL

Abstract

We have grown [1 nm/ 1nm]$_{n }$ superlattices of manganite (n = 20, 30,40) in which La$_{1-x}$Ca$_{x}$MnO$_{3}$(x=0.33) serves as the ferromagnetic layer while La$_{1-x}$Ca$_{x}$MnO$_{3}$(x=0.5) serves as the spacer layer on LaAlO$_{3}$ substrates by magnetron sputtering. The samples were characterized by XRD, Magneto-transport measurements, Rutherford backscattering spectroscopy, and atomic force microscopy. Enhanced longitudinal magnetoresistance (MR) under an applied field B, defined as MR (B) = $\rho $(B)/$\rho $(0) -- 1, was as much as -49{\%} at B=0.5 Tesla and T=90 K. The causes for this enhancement not seen at low field in other single-layered films of x=0.33 and the correlation of oxygen annealing with the MR effects for the superlattices will be discussed.

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Authors

  • P.V. Wadekar

    • Department of Physics and Texas Center for Superconductivity, University of Houston, Houston, TX
    • Department of Physics and Texas Center for Superconductivity, University of Houston,TX
    • Department. of Physics \& Texas Center for Superconductivity, University of Houston, Texas, 77204, USA

  • Q.Y. Chen

    • Department. of Physics \& Texas Center for Superconductivity, University of Houston, Texas, 77204, USA

  • O. Lozano

    • Department. of Physics \& Texas Center for Superconductivity, University of Houston, Texas, 77204, USA

  • P.V. Chinta

    • Department. of Physics \& Texas Center for Superconductivity, University of Houston, Texas, 77204, USA

  • W.K. Chu

    • Department. of Physics \& Texas Center for Superconductivity, University of Houston, Texas, 77204, USA

  • D. Wijesundera

    • Department. of Physics \& Texas Center for Superconductivity, University of Houston, Texas, 77204, USA

  • C.S. Lin

    • Deptartment of Physics \& Center for Nanoscience and Nanotechnology, National Sun Yat Sen University, Kaohsiung, Taiwan, Republic of China

  • P.H. Tseng

    • Deptartment of Physics \& Center for Nanoscience and Nanotechnology, National Sun Yat Sen University, Kaohsiung, Taiwan, Republic of China

  • Y.T. Lin

    • Deptartment of Physics \& Center for Nanoscience and Nanotechnology, National Sun Yat Sen University, Kaohsiung, Taiwan, Republic of China

  • L.W. Tu

    • Deptartment of Physics \& Center for Nanoscience and Nanotechnology, National Sun Yat Sen University, Kaohsiung, Taiwan, Republic of China

  • C.P. Lin

    • Deptartment of Physics \& Center for Nanoscience and Nanotechnology, National Sun Yat Sen University, Kaohsiung, Taiwan, Republic of China

  • H. Chou

    • Deptartment of Physics \& Center for Nanoscience and Nanotechnology, National Sun Yat Sen University, Kaohsiung, Taiwan, Republic of China

  • C.C. Kuo

    • Deptartment of Physics \& Center for Nanoscience and Nanotechnology, National Sun Yat Sen University, Kaohsiung, Taiwan, Republic of China

  • N.J. Ho

    • Deptartment of Materials and Optoelectronic Sciences and Center for Nanoscience and Nanotechnology, National Sun Yat-Sen University, Kaohsiung

  • H.W. Seo

    • Department of Physics, University of Arkansas, Little Rock, AR 72204